The present invention relates to high-efficiency motor/pump systems for jetted baths/spas and, more particularly, to an improved cost-efficient motor/pump system having a motor specially suited for jetted baths/spas.
Historically, the motor/pump assemblies employed with jetted baths and spas have used a conventional standard-frame induction motor to drive a radial flow pump. The manufacturers of induction motors have developed industry-wide standardized xe2x80x98classesxe2x80x99 that define motor characteristics including power, torque, and frame sizes. Many electric motors used in the jetted bath/spa industry are of the split-phase capacitor-start type in which a capacitor in series-circuit with a starting winding creates a rotating magnetic field during start-up. Typically, a centrifugal switch disconnects the capacitor when the motor is at speed.
The creation of the xe2x80x98standardizedxe2x80x99 classes with common frame sizes has presented the market with motors that have the same or nearly the same performance characteristics in a narrow price range. However, the standardized motor, which is suitable to a wide range of applications, has deficiencies when used in the jetted bath/spa market.
The requirements for motors that drive the pumps in jetted baths and spas are such that the forward end of the motor must be shielded from leakage of any fluid that leaks from the pump and, additionally, the motor should be cooled by forced air. Because the water that is used in jetted baths and spas often includes various types of detergents, soaps, bacteriacides, and other additives, it is critical that the interior of the motor be protected from the water. Additionally, it would be beneficial if the structure of the pump and the motor could facilitate the time-efficient assembly of the components at the time of manufacture.
In general, one of the most common failure modes for the motors is the malfunction of the centrifugal switch that interrupts the capacitor-start circuit when the motor is at speed. Since the motors/pump assemblies are typically installed as a xe2x80x9cbuilt-inxe2x80x9d at the time of building construction, replacement or repair of a faulty centrifugal switch can be a difficult and time consuming task.
Accordingly, a need exists for a motor/pump system for use in jetted baths and spas by which the system is cost efficient and particularly suited to provide reliable operation in the bath and spa environment.
In view of the above, it is an object of the present invention, among others, to provide a high-efficiency motor/pump system for jetted baths/spas.
It is another object of the present invention to provide a high-efficiency motor/pump system for jetted baths/spas in which the starting capacitor used to start the motor remains in the motor circuit during both the start and run modes of the motor.
It is still another object of the present invention to provide a high-efficiency motor/pump system for jetted baths/spas having a housing structure that minimizes the probability of water leaking from the pump from entering the motor.
It is a further object of the present invention to provide a high-efficiency motor/pump system for jetted baths/spas having a rear housing designed to conduct fan-driven cooling air over the exterior surface of the motor to effect cooling thereof.
It is a still further object of the present invention to provide a high-efficiency motor/pump system for jetted baths/spas in which the design facilitates efficient assembly of the components.
In view of these objects, and others, the present invention provides a high-efficiency motor/pump system for jetted baths/spas including a water pump having an inlet and an outlet for connection to the associated piping and a motor for driving the pump. The motor is a capacitor-start single-phase induction motor in which the capacitor is in series circuit with an auxiliary coil to provide a starting torque. The capacitor is kept permanently wired in circuit with the starting coil to eliminate the need for a reliability reducing cut-out switch and to simplify manufacture. The forward portion of the motor housing is designed to minimize the possibility of water entering the motor housing, and the rear portion of the motor housing is designed to direct cooling air over the exterior of the motor. Additionally, the forward portion of the motor and the rearward portion of the pump are provided with telescoping structures designed to enhance time-efficient self-aligned connection between the motor and the pump at the time of assembly.
The present invention advantageously provides a high-efficiency motor/pump system for jetted baths/spas in which the start-up switching normally associated with these types of pumps is eliminated to increase reliability, in which the possibility of water leaking from the pump and entering the forward portion of the motor is reduced, and in which the pump motor is cooled by a forced air flow over the exterior of the motor stator.
Other objects and further scope of applicability of the present invention will become apparent from the detailed description to follow, taken in conjunction with the accompanying drawings, in which like parts are designated by like reference characters.